Potential Difference
The potential difference is the difference in voltage. There must be a potential difference for a charge to flow across the end of a conductor.
Electric Current
Electric current is the flow of electric charge, measured in amperes (A). A wire carrying a current does not have a net electic charge, it is zero.
Voltage Source
A voltage source is an electirc pump that provides a continuous potential difference so the current can flow.
Electric Resistance
Electric resistance is the resistance that the conductor offers to the flow of charge. It depends on the conductivity of the material used in the wire, and also the length and thickness of the wire. Thick wires have less resistance than thin wires. Shorter wires have less resistance than longer ones. The temperature also effects electirc resistance, the higher the temperature, the more resistance. Electirc resistance is measured in ohms
Ohm's Law
States that the current ina circuit is directly proportional to the voltage impressed across the circut and is inversely proportional to the resistance of the circiut.
Currrent = voltage/resistance
1 ampere = 1 volt/ohm
The equation is also expressed by I = V/R
Alternating Current
Alternating current (AC) electrons in the circuit move first in one direction and then in the opposite direction, alternating back and forth about fixed positions. This is done by altrenating the polarity of voltage at the voltage source. Nearly all North American circuits involve voltages and currents that alternate back and forth at about 60 cycles per second.
A battery opperated device uses dc, so an ac-dc convertor is necessary to use it. A convertor uses a diode, a tiny electronic device that acts as a one-way valve to allow electron flow in only one direction. Only half of each cycle will pass through a diode because alternating current vibrates in two directions and it cuts off one direction of current. A capacitor is used to maintain a continuous current.
Electric Current
Potential Difference
The potential difference is the difference in voltage. There must be a potential difference for a charge to flow across the end of a conductor.
Electric Current
Electric current is the flow of electric charge, measured in amperes (A). A wire carrying a current does not have a net electic charge, it is zero.
Voltage Source
A voltage source is an electirc pump that provides a continuous potential difference so the current can flow.
Electric Resistance
Electric resistance is the resistance that the conductor offers to the flow of charge. It depends on the conductivity of the material used in the wire, and also the length and thickness of the wire. Thick wires have less resistance than thin wires. Shorter wires have less resistance than longer ones. The temperature also effects electirc resistance, the higher the temperature, the more resistance. Electirc resistance is measured in ohms
Ohm's Law
States that the current ina circuit is directly proportional to the voltage impressed across the circut and is inversely proportional to the resistance of the circiut.
Currrent = voltage/resistance
1 ampere = 1 volt/ohm
The equation is also expressed by I = V/R
Alternating Current
Alternating current (AC) electrons in the circuit move first in one direction and then in the opposite direction, alternating back and forth about fixed positions. This is done by altrenating the polarity of voltage at the voltage source. Nearly all North American circuits involve voltages and currents that alternate back and forth at about 60 cycles per second.
A battery opperated device uses dc, so an ac-dc convertor is necessary to use it. A convertor uses a diode, a tiny electronic device that acts as a one-way valve to allow electron flow in only one direction. Only half of each cycle will pass through a diode because alternating current vibrates in two directions and it cuts off one direction of current. A capacitor is used to maintain a continuous current.
Electric Power
Electric power the rate at which electric energy is converted into another form such as mechanical energy, heat, or light.
electric power = current × voltage → 1 watt = 1 ampere × 1 volt
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